function isSquare(s) {
    return Math.floor(Math.sqrt(s)) == Math.sqrt(s)
}

function isSquare1(n) {
    return Math.sqrt(n) % 1 === 0;
}
const isSquare2 = n => Number.isInteger(Math.sqrt(n));
var isSquare3 = function(n){
    return /^[0-9]+$/.test(Math.sqrt(n))
  }
console.log(isSquare(25))